The efficient production of prototype three-dimensional compositions or objects can provide an effective means of reducing the time it takes to bring a product to market at a reasonable cost. A typical approach for preparing prototypes has required specific tooling, such as molds and dies, which can be a slow and cumbersome process.
Recently, computerized modeling has alleviated some of the need for building prototypes by providing a good idea of what a product will look like without a specialized tooling requirement. However, the fabrication of a tangible object is still often preferred for prototyping. The merging of computer modeling and the physical formation of three-dimensional objects is sometimes referred to as solid free-form fabrication.
Solid free-form fabrication (SFF) is a process whereby three-dimensional objects, for example, prototype parts, models, working tools, production parts, molds, and other articles are manufactured by sequentially depositing layers of a structural material. Computer aided design (CAD) is commonly used to automate the design process. Using a suitable computer, an operator may design a three-dimensional article and then create that object by employing a positionable ejection head that selectively emits structural material. Various techniques that employ SFF have been explored.
Traditional methods of forming SFF objects include using rapid jetted polymer systems, extrusion nozzles, and powder/binder based systems. All of these systems have decreased the time traditionally required to produce desired three-dimensional objects, yet the jetted and extrusion-based systems are still relatively slow processes due to the necessity of ejecting 100% of the build and support materials through selective dispensing nozzles. Additionally, material properties and surface finish are often compromised in existing methods due to material compositions and porosity created in the resulting three-dimensional objects. Moreover, the temporary materials required to support the structure during fabrication are often difficult to remove, require extra time and labor, and may cause variations in surface finish quality.